Power-transmitting device.



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SAMUELW. RUSHMORE, OF PLAINFIELD, NEW JERSEY.

POWER-TRANSMITTING DEVICE.

SPECIFICATION forming' part of Letters Patent No. 784,352, dated March'7, 1905.

Application filed April 27, 1904. Serial Nn. 205,058.

To all whom. 'it www concern:

Be it known that I, SAMUEL 1V. RUsHMoRE, a citizen of the United States,residing at Plainfield, in the county of Union and State of New Jersey,have invented certain new and useful Improvements in Power-Transmitting.Devices; and 1 do hereby declare the following to be a full, clear, andexact description of the invention, suchas will enable others skilled inthe art to which it appertains to make and use the same.

y invention relates to a variable-speed power-transmitting device havinga driving and a driven shaft in which different rates of speed of thedriven shaft are obtained by shifting a gear on one shaft in turn intomesh with one or the other main gears -of different diameter fixed onthe other shaft, sometimes called changeable-gear mechanism. The maing'ears and the sliding gear are of course arranged on different shaftsand on one or the other, as may be most convenient. As here shown, themain gears are on the drivingshaft and the sliding' gear on the drivenshaft. As now commonly constructed in such mechanisms used with autocarsor elsewhere when a sudden change in speed or a change from rest tospeed is effected on account of the inertia a severe strain and a heavyshock is imposed on these gears, so that the teeth are often broken orstripped, and commonly the corners of the teeth are quickly worn out,because the sliding gear is not immediately thrown into completeengagement.

My invention consists in arranging yielding gears in front of the maingears of different diameters, with which yielding gears the sliding gearfirst engages, so that by such preliminary engagement the speed of theshaft is accelerated or retarded and the gears are brought more or lessto a similar or equal peripheral speed before the engagement-with themain gears, and the main gears are thus largely relieved of shock andstrain.

My invention will be understood by reference to the drawings herewith,in which the reference letters and numerals of the specificationvindicate the corresponding parts in all the figures.

Figure I is a longitudinal section of a changeable-gear mechanism.illustrating my invention. Fig. Il is a fractional section, and Figs. H1and 1V are isometric views of a change in construction adapted toaccomplish the same result.

V1n the figures, A indicates the driving and B the driven shafts,suitably journaled ina case 1, the latter carrying the sliding gear 2,fixed to rotate with the shaft and being' a compound gear a of differentsizes. This is provided with a circumferential groove 4, with whichengages the antifriction-rollers 5 on the forked ends of power-lever G,fixed on sliding' shaft 7 and operated by hand-lever 8, suitablyarranged and supported on a suitable arm 10. Said hand-lever may engagewith the sliding shaft by means of slot 11. and pin 12. Any othersuitable means may be provided for sliding the sliding gear, and it isevident that this sliding gear may be fixed on its` shaft and said shaftmoved to vary position of sliding gear.

On the d riving-shaft are fixed the main gears 13 and 14 of differentdiameters to mesh, respectively, with compound sliding gear a. b for lowand high speed, respectively. There may be two, three, or more of thesemain gears for different speeds and reverse. On the side or sides ofthese main gearsare arranged my yielding' gears, with which the slidinggearteeth first engage to begin the rotation or to diminish or toincrease the speed of the d riven shaft. 1n Fig. l. these yielding'gears l5 16 16 are held in frictional engagement with the shaft byanysuitable means. As here shown, they are forced, respectively, intofrictional engagementwith the conical or tapering hubs 17 18 18 on themain gears by suitable springs Q0 21, the latter being held in positionon the shaft A by collar 22, so that as the sliding' gear is thrown intoengagement with one or the other of these yielding gears the inertia isovercome, the speed of the driven shaft in a measure accelerated orretarded, and before the parts can be exposed to excessive strain or toinjury the yielding' gears will slip on the conical hubs.

30 indicates the engine-shaft; 31 and 32, re-

spectively, the female and male members of a friction-clutch which isoperated to transmit the power by the engagement of antifriction-rollers33 of a forked lever`34 with the circumferential groove 35 on the hubs36 of the male element, also carrying a fork-or claw 38, engaging with acorresponding fork or claw 89, fixed on the end of the drivingshaft A.

To guard against partial engagement of the sliding gear with the maingears and the danger of breaking off the corners of the teeth, I haveprovided means for ,suddenly accelerating the longitudinal movement ofthe sliding shaft, and thereby effecting the instantaneous and completeengagement of the sliding gear with the main gear-namely. asuitablespring 41-and inclines or notches 42 42 on the sliding shaft 7 fitted toengage with the spring, whereby as the shaft is moved and the slidinggear approaches the' engaging position the movement of the sliding shaftis accelerated and the sliding gear instantaneously forced intoengagement.

Instead of accomplishing the result by frictional engagement of theyielding gears with the main gears a similar result may be accomplishedby providing them With yielding or resilient teeth 46, as shown in Fig.III, or even constructing them in the form of cylindrical metallicbrushes 56, by which a yielding but sufiicient engagement first takesplace with the sliding' gears to overcome the inertia. When my yieldinggears (or gear-like elements) are so formed, they could be keyed orotherwise fixed on the shaft, as showny in Fig. II, it being sufficientif their peripheral portions afford a yielding engagement and notnecessary for the entire yielding gear to slip on the shaft.

I do not propose to limit myself to the form and arrangement of partshere shown, as they may be varied without departing from the spirit ofmy invention.

Having thus described my invention, what I claim, and desire to secureby Letters Patent, isy 1. In a power-transmitting mechanism, thecombination with a suitable support, of parallel shafts, a series ofgears fixed on one shaft, a sliding gear fitted to turn with the othershaft and adapted to be moved longitudinally, means to move the slidinggear into engagement with the fixed gears, and yielding gearlikeelements arranged on the first shaft at the sides of the fixed gears,first to engage with the sliding gear.

2. In a power-transmitting mechanism, the combination with a suitablesupport, of parallel shafts journaled therein, a series of main gearsfixed on one shaft, a sliding gear fitted to turn with and slide on thesecond shaft, means to slide the sliding gear on its shaft, andyielding' gears carried on the first shaft and maintained in frictionalengagement with the respective fixed gears to engage with the slidinggear before it is moved in to'engagement with the fixed gears.

3. In a power-transmitting mechanism, the combination with a suitablesupport, of parallel shafts journaled therein, a series of main gearsfixed on one shaft, said gears being provided with tapering hubs, asliding gear on the second shaft, means to move the sliding gear intoengagement with the fixed gears, and yielding gears fitted to thetapering hubs and frictionally engaging therewith.

4. In a power-transmitting mechanism, the combination witha suitablecase, of two parallel shafts journaled therein, a series of main gearsof different sizes fixed on the first shaft, said gears having taperinghubs, a slidinggear element fitted to slide on and turn with the secondshaft, gears of different size on the sliding-gear element to engagewith the respective fixed gears, means to slide the sliding element,yielding gears fitted to the tapering hubs, and springs to force theyielding gears into frictional engagement with the hubs.

5. In a power-transmitting mechanism, the combination with a suitablecase, of a drivingshaft journaled therein, means to connect said shaftto the source of power, a parallel driven shaft journaled in the case, aseries of gears of dierent sizes fixed on the driving-shaft, said gearshaving tapering hubs, a sliding element fitted to slide on and turn withthe driven shaft, a series of gears of different diameters on thesliding element to engage with the respective fixed gears, yieldinggears fitted to said hubs, and springs arranged on the shaft to maintainthe yielding gears in frictional engagement with the hubs.

6. In a changeablegear mechanism for transmitting power, the combinationwith a suitable case, of two parallel shafts journaled therein, gearsfixed on one shaft, asliding-gear element fixed on the second shaft,asliding bar fitted in the case and having inclined portions, an armfixed on said bar and engaging with the sliding element, and a springarranged to engage with the inclined portion to accelerate thelongitudinal movement of the bar and the engagement of the gears.

7. In a power-transmitting mechanism, the combination with a suitablesupport, of two parallel shafts journaled therein, a series of maingears of different sizes fixed on one shaft, a sliding gear fitted toturn with the other shaft, means to move the sliding gear gears, andmeans to accelerate the movement of the sliding gear at the point ofengagement, to effect a rapid and complete engagement of said gears.

8. A power-translnitting mechanism having adriving-shaft and a drivenshaft, one or more gears rigidly secured on one of the shafts, gearsslidably mounted upon the other shaft, to be moved into or out of meshwith the fixed gear .LOO

IIO

4into and out of engagement with the main or gears-means foraccelerating or retarding the speed of one of the shafts so that thegears may be brought approximately to the saine peripheral speeds beforebeing thrown into mesh. i

9. In a variable-speed, power-transmitting mechanism the combination ofa shaft, one oi' more main gears rigidly attached thereto, a secondshaft, one or more sliding gears fitted to rotate with the second shaftand capable of endwise movement, said sliding gears beingadapted to meshwith the main gear oi' gears on the first shaft and yielding gearsarranged to be brought into mesh to accelerate or retard the speed ofone oi' the other of the shafts so that the main and sliding' gears maybe brought approximately to the same peripheral speeds before being'thrown into mesh.

l0. In avariable-speed, power-transmitting device, a shaft, one or moregears rigidly attached thereto, a second shaft, one or more slidinggears fitted to rotate with the second RUSHMORE.

